1. Field of the Invention
This invention relates to an optically active cyanobiphenyl compound useful as a component of nematic liquid crystal composition.
2. Description of the Prior Art
The liquid crystal composition is used for display elements of twisted nematic (TN) type, super twisted nematic (STN) type and cholesteric-nematic phase transition type.
Optically active compounds such as (S)-4-cyano-4'-(2-methylbutoxy)biphenyl are added into the nematic liquid crystal composition used for above mentioned display device to induce the suitable helical pitch.
However, the effects of known optically active compounds are not sufficient yet and the induced helical pitch shows large temperature dependence.